The situation: you are backpacking and are above timberline. Streams are ubiquitous, you are well equipped so exposure is not a problem, the entire party is uninjured and healthy. But a large, rapidly expanding forest fire sprang up well after you left the trailhead, and your route down is blocked. You have some food, but you will be on short rations if you have to take a long detour to get down. (See option 2, below.)

Do you (1) activate your PLB (see definition of PLB at the end of the Question); (2) climb up to a pass and try to identify a fire-free way down on the other side of the pass, and activate your PLB only if you cannot find what looks like a safe way down from the pass.

Option (2) seems to me to be clearly the best, but are there dangers to doing this? (The climb up is well within your capabilities.) Under what conditions would Option 1 be best?

Addendum: See How long after a forest fire can you safely reenter a forest?.

Edit in Response to Comment: Personal Locator Beacon (PLB) is a [portable] emergency radio locator beacon ..... capable of providing homing signals to assist search and rescue operations. Many hikers and backpackers routinely carry a PLB to ensure rescue if they get in a life threatening situation, e.g., alone with a broken hip days from the trailhead.

  • 23
    The PLB should be for situations immediately dangerous to your life. Being possibly short of food on a detour is not that. However, intense thick smoke conditions and flying embers could well be a reason. Aim for a forest road and you will find firefighters. (In my experience they like Oreo cookies, so plan on saving those for them).
    – Jon Custer
    Commented Aug 9, 2018 at 16:20
  • 2
    Forest fire does not last long in a specific area. When the wood is burnt the fire goes out. Hike against the fire for what out.
    – paparazzo
    Commented Aug 9, 2018 at 16:22
  • 4
    May I add to the situation that it is possible that there will be no vehicle remaining at the trailhead; if the fire consumes it or it must be towed to make way for fire crews. How much more food will be required to return to civilization? <- This question is rhetorical and no answer is needed.
    – Jammin4CO
    Commented Aug 9, 2018 at 19:43
  • 3
    I think it would help if you explained what a PLB is, and why you'd have one.
    – jamesqf
    Commented Aug 10, 2018 at 17:33
  • 1
    @EricDuminil - It's what us woodsy-types call Personal Locator Beacons
    – Valorum
    Commented Aug 11, 2018 at 20:39

5 Answers 5



Your option 2 is best, but having said that, rescue crews will want to know you're out there sooner than later.

In the option 1 you described, you would be activating your PLB, then waiting for rescue above the treeline. Fire doesn't go very far above treeline, but smoke, ash, embers and heat do. Just because you're above the treeline doesn't mean you're guaranteed to be safe from the fire, you just won't likely get burned to death, but death by flames isn't the only way to die in a forest fire.

When the Kenow wildfire burned 38,000 hectares of forest last summer, the ash from the fire was piling up in my back yard 50km away. Air quality was so bad that we had to stay indoors with all the windows closed, and the sun was blotted out for weeks. If you are on a mountain directly above a blazing forest fire, your odds of dying from smoke inhalation are pretty good, but breathing in a hot breath of superheated air is what usually kills people trapped by fire.

The situation you described is the exact reason why parks require people to buy backcountry permits to go backcountry camping. Park staff need to have a record of how many people are deep in the backcountry, so they know in a situation like a forest fire how many people they need to evacuate. If you're going to a spot where they don't require permits, then make sure someone knows where you are, or at the very least leave a note on your vehicle indicating where you have gone and when you expect to return.

If you are in the backcountry and discover a fire, you must report it immediately, especially if you are above the fire and it has you cut off from your escape route. You're best chance of surviving a fire is to reatreat! If you are on top of a mountain, this means getting off the mountain. Do not hang out on the rock and expect you're going to be safe, you need to get off that mountain as fast as you can, if you know of an alternate route, take it. Rations are the least of your concerns when running from a wildfire. You can survive days without food and water, but you will not survive breathing in unrelenting plumes of smoke or superheated air. (One caution with descending a mountain is to choose your route wisely; if you get ledged-out on the decent you can get yourself in just about as much trouble as being stuck in the path of a fire.)

In any case, your first course of action should be to call for help, if you have no means of contacting Emergency Crews, and no way to evade the fire, then use your PLB. Rescue crews will want to know that you are out there. The problem with using your PLB is that once you deploy it you typically need to hang around in one spot in order for rescue crews to find you. If you're in the smoke however, it's unlikely they will ever find you, so deploying it is not going to help you get found unless you can get out of the smoke to somewhere open and visible.


Option 2 is better, as activating your PLB will divert resources that could be used to fight the forest fire, and put other people in unnecessary danger (PLBs aren't a get out of danger free card).

Fires rarely go above tree line,

Alpine tundra areas in the [Colorado] San Juans rarely burn because, according to Korb, they are typically sparse in fuel, and cool night temperatures bring increasing humidity which makes them wetter in than lower elevations.


and even then would be no where near as intense as below treeline where there are trees to burn.

Do note that fire tends to spread downwind, so hiking upwind is the better option.

Also, people can hike farther on short rations much longer and farther than they might think and even if you all but run out, you can still go quite a long ways.

  • 6
    Another reason to go upwind is to avoid the smoke. Breathing hot and thick smoke is bad for one's health! Commented Aug 10, 2018 at 8:57

Your question answers itself - "above timberline" indicates very little, if any, fuels for the fire, so the best option (assuming no life-threatening issues) is to stay put. As others have mentioned, forest fires move rapidly, so you'll be able to descend at some point. Also fires are heavily monitored by a wide variety of wildland firefighters, so you may run into staff or be seen from the air (in a clear area that is typical of being above the timberline) by survey or fire-related aircraft.

Descending into an area freshly burned can be very dangerous, however. A number of experienced wildland firefighters are struck (often fatally) every year due to "snags" - trees that have been weakened by the fires and are prone to falling without any warning or sound. If you must venture into a burned area, keep your head on a swivel and do not linger, for any reason!

  • 7
    Another hazard is stepping into hot coals in underground cavities left behind by burned stumps and roots. They can burn a long time underground. Commented Aug 10, 2018 at 21:02

If you are not threatened there is no reason to activate your PLB. See How bad do circumstances need to be before activating a PLB?

It is a forest fire, there may be people who are actually at risk for their lives, activating your PLB where there is no real risk to your party, may cause the diversion of resources, that result in loss of life to others.

Presumably you registered at the trailhead, and you have a friend who knows where you are. There should be aircraft in the area soon attempting to identify your location and risk level.

EDIT I am pretty sure the likelihood of the registry burning before the rangers have a chance to retrieve it, is extremely low. Posted this follow up question Will the Trailhead Registry burn in a forest fire?

  • 9
    The trailhead registry will probably burn in a forest fire.
    – gerrit
    Commented Aug 9, 2018 at 17:17
  • related. I might also mention ways to communicate your status with the aircraft.
    – user8348
    Commented Aug 9, 2018 at 17:52
  • 1
    @gerrit We can only hope they get ahead of the fire can check the registry.
    – paparazzo
    Commented Aug 9, 2018 at 20:26

A forest fire moves fairly rapidly (like 6-10 mph). Once it consumes the vegetation it goes out. If you stack a fire pit at best it will burn for a day. Just wait a day or two and walk out. Yes there will be some smoldering trunks and roots. In a large remote fires hot shot crews will protect home by home and let the fire pass.

  • 15
    I'm skeptical if this is a good idea considering how hazardous the ground could be if you follow the fire's wake. Even if there is not a fire burning on the surface, fire could be burning underground and/or the ground beneath you is more likely to give out than where fire has not just blazed through.
    – cr0
    Commented Aug 9, 2018 at 21:06
  • 3
    I can't find the question but there was one here in the past about how long one needs to wait after a forest fire before walking around in the burned area. Most answers were "if you don't need to, don't for a while (months)". Maybe in this case the hikers would need to, but I'm still not sure it should be plan A or B or...
    – cr0
    Commented Aug 9, 2018 at 21:07
  • also (@cr0) I'd be concerned about carbon monoxide from residual smouldering
    – Chris H
    Commented Aug 10, 2018 at 15:22
  • 2
    @ChrisH Residual CO in a open environment? Does a camp fire worry you?
    – paparazzo
    Commented Aug 10, 2018 at 21:49
  • 2
    Not residual CO, residual smouldering, over large areas. A campfire doesn't worry me in the slightest, but being surrounded by their glowing remains with no way of getting upwind would be a better model for the aftermath of a fire.
    – Chris H
    Commented Aug 11, 2018 at 13:00

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.